Alcohol denaturant and process of preparing it



Get. 2, 1934.

L. J. FIGG, JR

ALCOHOL DENATURANT AND PROCESS PREPARING IT Filed Aug. 11, 1932 A wooomsmumow semme mus PYROUGNEOUSI CRUDE STILL CRUDE 4 Em AC! SOLUBLE l cramMETHANOL A YI l 011 acenc m mous ACID snu. ms nsmm mwnou 50% ME 0L e-yzmAND Acm ans J y OILS cnnson mums or 0mm EXTRACTOR ALCOHOL ons l @flgtncACID uenY ACID OILS 50% MEWNOL ALCOHOL ous a TED WASHING 0F Mum-comm" Ao ons usm' OIL-S snu. LIGHT on W M LIGHTACID ALLYL ALCOHOL ALCOHOL OILSTILL STILL omsnu.

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amass Ger. 2, recs sarsar osrica ALCDHOL DENATURANT AND PROCESS OFPREPARING IT Louis J. Figs, J32, King sport, Tenn, assignor to EastmanKodak Company, Rochester, N. Y., a corporation of New York ApplicationAugust 11,1932, Serial No. 828,381

16 Claims. (01. 202-77) This invention relates to the denaturing ofethyl alcohol, to compositions for use as denaturants, to alcohol sodenatured, and to a process of preparing the denaturant.

In my application Serial Number 562,267, filed September 11, 1931, Idescribed a denaturant for ethyl alcohol comprising the washed alcoholoils obtained from wood distillation, namely that resulting from thecrude methanol separated from pyroligncous crude. While the denaturanttherein described is of great value and makes ethyl alcohol unpalatable,I have now been able to prepare a denaturant which is even moredifficult to separate from the alcohol comprising it than the denaturantdescribed in the foregoing application.

While no one to my knowledge has ever been able to prepare a denaturantfor ethyl alcohol which will completely defy separation, the de- 24}naturant constituting the instant invention is of such an unpalatablecharacter and is so difficult to separate from the ethyl alcohol, thatit is totally impractical for the bootlegger to divert alcohol denaturedwith it into illicit alcohol trade. My denaturant has the advantage thatit does not ruin the alcohol for the legitimate industry, such as thelacquer trade, and is non-toxic and non-poisonous, so that in the eventalcohol containing it should be taken internally by mistake or ulteriordesign, it will not cause the death of the imbiber. The effectiveness ofthis denaturant is evidenced by the recent approval thereof as adenaturant by the U. 8. Bureau of Industrial Alcohol.

It is an object of my invention, therefore, to provide a denaturant forethyl alcohol which makes impractical and unpalatable the use of suchethyl alcohol as a beverage and yet which is non-toxic, non-poisonousand free from methyl alcohol, heretofore so much dreaded by the industryas a denaturant. A further object of 'my invention is to provide aprocess for the preparation of that denaturant. Another object of myinvention is to provide effectively denatured ethyl alcohol. Furtherobjects will appear to those skilled in the art upon a perusal of thisspecification.

I have found that by combining the light acid oil fraction, the allylalcohol fraction and the so washed alcohol oil fraction frompyroligneous crude that a most effective denaturant can be provided.These three fractions are effective as a denaturant merely by mixingthem in suitable proportions with each other and then adding the imixture to the ethyl alcohol to be denatured, or

suitable proportions of each of the three fractions may be addeddirectly to the alcohol to be denatured, or suitable proportions of thethree fractions may be mixed with a suitable proportion of a suitablecarrier, such as acetone, ethyl alcohol, isopropyl alcohol, isopropylether, ethyl methyl ketone, normal propyl alcohol, or other loweralcohol (except methyl), lower ether, or similarly suitable solvent forthe three denaturing fractions. Generally speaking, I have found anorganic solvent boiling between C. and 99 C; as suitable, although I amnot to be limited to that range as it is only illustrative and otherswill occur to those skilled in the art. This solution of denaturant maythen be added to the ethyl alcohol to be denatured. Similarly, I mayemploy a mixture of any two of these fractions, more particularly theallyl alcohol fraction with either of the oil fractions, or I may employ(less desirably, however) any one of the fractions singly. Preferably,however, these three fractions (or less desirably, any two or any one ofthem) are fed into a reflux column together with a suitable proportionof one ofthe carriers above named, such as ethyl alcohol, whichrefluxing yields a product consisting of, or comparable to, anazeotropic mixture of the three fractions with the carrier, which is aneven more effective denaturant than the mere mixture of the threefractions. This refluxing alsopermits.

the elimination of volatile organic acids, corrosive contents of theoils and most of any ob- Jectionable color and odor connected therewithby suitable saponification, such, for instance, as by the addition of aweak alcoholic solution of sodium hydroxide to the reflux column.

The manner in which these three fractions are produced, combined andrefluxed will be fully understood from the following description whichis sufficiently illustrative of the manner of carrying out my inventionto inform those skilled in the art thereof but by which I do not intendmy invention to be limited, such limitations being imposed only by theclaims appended hereto.

In the drawing accompanying this specification and forming a part hereofI have illustrated, by a combined flow sheet and diagrammatic sketch,one method by which my invention may be realized.

The production of crude acetic acid and crude methanol by thedistillation of hard wood is well known to those skilled in the art andneed not be described here in detail. Hard wood cuttings are distilledin suitably heated retorts, giving off a pyroligneous crude, which afterthe settling out I or requiredtobe recoveredby an additional re- Thisalkaline wash also for of insoluble tars. in suitable settling tanks, iscon-. 7 I ductedthrough a bubble plate column still from the top ofwhich issues crude methanol and alco-:

' I 1101011, and from the bottom ofwhichissues crude acetic acidtogetherwith soluble tar and so-c'ialled acid oils.

i I This crude acetic acidsoil'mixture is conducted through: an aceticacid fractionating column or, I still from the bottom of which theremaining tar withdrawn or in the bottom of which the tar "collects, 6'to"l%- acetic acid together with acid oils issuing fromthestillas'vapors which are I I condensed and decantedr 'From the decanter the.6 to 7% aqueous acetic acid layer is withdrawn and conducted to furtherconcentration with I I whichwe are; not he're concerned; the light acid:

- T oillayer isalso withdrawn, these light oils bein coveryprocess.

washed by, for instance, thoroughly agitating 'with: equal proportionsof water to remove any remaining acetic acid, decanting, further-washingI with 1 to 2%sodium carbonatesolution and again I y I decanting; Only aweakalkaline solution is 'employed for such washing because if astrongeralkaline'solu'tion be 'employed, some :of the oilsare liabletobe: taken into solution and wasted the purpose of improving color; andremoving some cut. I

*Jncom-pounding my novel denaturant. I I

e i Returningnow to the crude methanol issuing, '40- from the crudepyroligneousf ;still,: this crude methanol isdiluted with sufllcientwater toproe 'duce approximately 30% methanol. I The mixture isthoroughly agitated after which two layers are allowed to separate. Theoily layer separates out on top, while the water layer is drawn off atthe bottom as 30% methanol. These alcohol oils are then washed with anequal proportion of water, the water decanted and the oil again washedwith a 1 to 2% solution of sodium carbonate, again decanted and thewashed alcohol 011 withdrawn. Here, as in the case of the washing of thelight acid oils, the alkaline solution should not be too strong as it isliable to dissolve or absorb some of the oils. This alkaline wash isalso for the purpose of improving color and re-- moving somepyroligneous impurities which may still be present.

The 30% methanol is conducted through a carbon'extractor of a type wellknown in the art, such as a tall steel cylinder about 10 feet high andtwo feet in diameter, filled with granular charcoal. This is done foreconomical reasons because of the fact that 30% methanol contains inadsorbed condition, small quantities of alcohol oils which have I notcompletely separated from the 30% methanol following the dilution of thecrude methanol with water. It is not essential that this carbonextractor be placed ln the line feeding the 30% methanol to the methanolstill, but it is described here in order to show the complete operationof the process. As the 30% methanol passes through this carbon extractorcertain oils are adsorbed by the activated charcoal. After the charcoalhas adsorbed about as much oil as it will hold, the current of 30%methanol is shut ofi and the adsorbed oils are liberated with 11W steam,the vapors condensed, and the oils allowed layer and recoveredtherefromand added to the liberated adsorbed .oils, this is notimportant. These liberated adsorbed alcohol oils may then be I I addedto the washed alcohol oils, which: oils are I to separate from: thewater by, stratification. I :While some alcohol oils maybe held inthewatery thcnconducted to analcohol oil column still from 1 l which an'alcoholoil fraction, having, a boiling, I

range between: approximately 51 and 1 60 G. is

withdrawn. I :This constitutes the alcohol oil frac- It will be:understood that the libertion; useful as thesecond element of. my novel,de- I naturant.

ated adsorbed oils fromthe carbon extractor are. of'the samegeneral'character as thealcohol oils- 'and'thjat they are utilizedmerelyas a matter of 7 economy; since they are carried over insolution II or suspension. in the 30% methanol and other-.

wise might bewasted or onlypartially utilized. I Accordingly, thealcohol oils are to-be understood :as being those liberated fromthe.crude methanol by dilution thereof to 30% methanol whether 1 thesealcohol .oils. are decanted off from the:di-

luted crude .methanol or obtained by liberation, from; the:carbonextractor, :or both. i This ,re finedalcoholoil fraction issubstantially that ;de-: 1 scribed and claimed in: my above referred tocor -pendingapplication. I I, .i ,V

The 30% methanol which passesthrough the I carbon extractor isconductedto a multi column 105. still I of known :type in, the industry.The more,

columns employed, the more eiliclent, of course, i"

I have found it preferable for greatest efficiencyto -cohol and,therefore, has no function in my denaturant. The methyl alcohol fractionand the methyl acetone fraction, likewise, have no place in my noveldenaturant. fraction is that normally referred to as Columblan spirits",being possibly 99 /2% methanol together with a little acetone. Themethyl acetone fraction is that well known to the industry, consistingof a mixture of methyl alcohol, acetone, and methyl acetate.

If one desires in connection with this distillation step to obtain pureacetone, it can be accomplished by adding to the foregoing column asolution of calcium chloride or sodium hydrogen sulflte, giving additionproducts formed by reaction of the calcium chloride or sodium hydrogensulfite with acetone, which addition products reflux down the column andcollect in the base, being later decomposed by steam distillation togive acetone, to gether, possibly, with some woody impurities, whichacetone is, however, free from methanol and may, therefore, be employedin connection with my denaturant if desired, as hereinafter pointed outwhen referring to acetone.

The crude allyl alcohol is subjected to distillation in a column still,from which is removed an allyl alcohol fraction having a boiling rangebetween approximately 66" and 91 C. This'allyl 84 0 101 f actioncontains no methanol, although 1 is the separation of the various:fractions and components ofthe, 30%methanoh Accordingly, 1 1 1 i6 employa fourcolumn fractionatin-g-still. 1 This T multi columnstillis-operated continuously, of

course, for greatest .efliciency'. From this multi column still underproperly controlled; conditions. know'n'to distillation: operators, maybe separated afraction of methyl alcohol, afraction of methyl acetoneand a fraction of crude allyl alcohol. De-

This methyl alcohol gel" it may contain a small percentage of acetonecarried over as an azeotrope. This allyl alcohol fraction constitutesthe third element useful in my novel denaturant.

As acetone (free from methanol) has some useful properties in mydenaturant, the amount which may be contained in the allyl alcoholfraction is not undesirable and I may even add further acetone (freefrom methanol) to this allyl alcohol fraction. Therefore, unlessotherwise designated, in referring to the allyl alcohol fractionhereinafter, it will be understood to optionally include a smallproportion of acetone, if desired.

At this stage I may now produce a denaturant which consists merely of amixture of these three major fractions above referred to. A veryacceptable denaturant may be compounded by mixing together equal partsof the three fractions, namely, the light acid oil fraction, the washedalcohol oil fraction and the allyl alcohol fraction. As I have foundthat a little smaller proportion of the light acid 011 and the allylalcohol fractions may be employed and still obtain an effectivedenaturant I may compound my denaturant by employing approximately threeparts of the washed alcohol oil, two parts of the light acid oil and 2.5parts of the allyl alcohol fraction. Many other mixtures in which eachfraction constitutes a substantial proportion, as, for instance, about20% or better, may similarly be utilized. In compounding the denaturantwith these three fractions in the ratios above mentioned or ratiosroughly similar thereto, I have found that somewhat better dispersion orsolution, of the denaturant in the ethyl alcohol to be denatured, occursif there be added to the denaturant in the mixing thereof approximatelyten parts of acetone. I may further dissolve the mixture of thethreefractions with or without the added acetone in any desired quantity ofethyl alcohol, such as with equal parts of ethyl alcohol or even withlarger quantities of ethyl alcohol, for instance, 8 to 10 parts whichfinal solution may then be employed as the actual denaturant to be addedto ethyl alcohol at the producer's plant under government supervision,such as from one to ten parts of the denaturant to 100 parts of theethyl alcohol to be denatured, depending upon the dilution of the threefractions with acetone or ethyl alcohol.

As pointed out in my above mentioned application. the washed alcoholoils themselves make an acceptable denaturant but I have found that incombination with a suitable proportion of the allyl alcohol fraction,preferably plus some acetone, a very effective denaturant is produced.Similarly, the light acid oil fraction may be employed alone as aneffective denaturant or one may mix therewith suitable proportions ofthe allyl alcohol fraction to obtain a better denaturant. I may alsoemploy a mixture of the alcohol 011 fractionfand the light acid oilfraction. but this is not as effective as either or both of thesefractions with the allyl alcohol fraction added thereto. In theforegoing mixtures, equal parts may be employed or minor proportions ofthe allyl alcohol fraction may be used for compounding with either ofthe other fractions. As adverted to earlier herein, I may employ othersuitable carriers besides ethyl alcohol. Therefore, in making a mixeddenaturant I may use acetone, isopropyl alcohol, isopropyl ether, ethylmethyl ketone, normal propyl alcohol, or other carrier in this class asthe carrier instead of or together with ethyl alcohol.

' I have found, however, that a denaturant of even more desirableproperties may be prepared by refluxing preferably the three fractionsabove referred to with one of the suitable carriers above named, such,for instance, as ethyl alcohol, in a manner of which the following isillustrative.

As shown by the accompanying diagram, a

multi plate column of any desired height is em-- the top thereof, sothat these fractions, being heavy, will reflux substantially the entirelength of the column. The allyl alcohol fraction is preferablyintroduced into the column somewhere near the center thereof, forinstance at approximately the tenth plate from the top of this sizecolumn. With the allyl alcohol fraction, I may introduce into the columnthe desired amount of acetone, in order that the allyl alcohol will morehomogeneously combine and reflux through the column with the remainingelements of my denaturant. Then, at about one third of the distance upthe column, as, for. instance, at the sixth or seventh plate from thebottom thereof, I introduce the desired amount of a suitable carrier,such as ethyl alcohol, to operate as a carrying agent, so to speak, forthe other elements of my denaturant.

Connected with the top of the column is a suitable water-cooledcondenser provided with a recondensate. A base heater is, of course,provided for the column, it being supplied by a draw-off 3 pipe from thebottom of the column, the top of the base heater, of course, beingconnected back to the column at about the second plate thereof, so as tocontinuously drive back into the column any vapors which should beincluded in the flnal product.

In addition, I have found it desirable to admit at the top of the columnin small amounts a relatively weak alcohol solution of caustic, such,for instance, as 10%. of sodium hydroxide in ethanol, although this is amatter of choice, depending upon the clarity and purity of the productdesired. The sodium hydroxide solution causes heavy woody impurities,such as would give a bad color and odor to the product, to be removedfrom the product although it will be understood that if color and odorare not important, this caustic reflux may be dispensed with.

The various fractions, together with the acetone and ethyl alcoholadmitted to the column are metered, such as by weirs, valves, meteringpumps, or the like, so that the proper proportions of the variouselements are admitted to the column to obtain a product having the mostdesirable properties of the various elements of the denaturant. One ofthe preferred embodiments of this form of my invention is to introduceinto the column in metered proportions somewhat as follows- Thetemperature of the column is so controlled that the completed product isdriven off from the top of the column at a rate of approximately 20gallons per minute, if a twenty plate column 6 feet in diameter is used.Approximately one-half of the condensate may be returned to the top ofthe column for refluxing back therein, and the admission of the variouselements to the column are so metered or controlled as to permit of theforegoing speed of operation. The ex-- tremely high boiling portions ofthe various fractions which are incapable of passing off from the top ofthe column, of course, reflux down to the base heater from which theymay be continuously or periodically withdrawn.

A striking discovery from the operation of the foregoing process is thatthe denaturant produced is actually an azeotropic mixture having asubstantially constant boiling point or range thereof, which is entirelydifferent from the elements contributing to that azeotrope. In otherwords, it will be observed that the-boiling points of the elementsentering into my invention range from approximately 51 C. to 160 C.

However, the denaturant produced in accordance with the foregoing methodhas properties differing from each of the elements and also differingfrom what would be expected from a mere mixture thereof. For instance,the product produced in accordance with the above preferred embodimentof my invention has a specific gravity of .82 at 60 F. and has a boilingrange commencing at 70 C. and ending at 80 C. The product gives a clearor only slightly opalescent solution when 10 cc. of alcohol denaturedtherewith (100 ing the denaturant.

parts of ethyl alcohol to parts of denaturant) is added to 90 cc. ofdistilled water. The acetone content, it will be apparent amounts toapproximately grams of acetone per 100 cc. of denaturant, although this,of course, depends entirely upon how much acetone is added to the refluxcolumn along with the other elements compris- The ester content of thedenaturant will be found to be exceedingly low, being in theneighborhood of one-half to one percent. Since the denaturant contains aproportion of unsaturated pyroligneous bodies, these may be tested byany of the various bromine absorption methods. The methanol content ofthe denaturant is practically nil. Full specifications of a desirabledenaturant made in accordance with my invention are set forth in Gen.Cir.

#117, July 8, 1932 of the Bureau of Industrial Alcohol, U. S. TreasuryDepartment.

Inasmuch as the active elements of my preferred denaturant comprise thethree fractions alluded to, it will be apparent that the acetone may beomitted from the refluxing operation, if desired, when employing any ofthe other carriers named. Likewise, the acetone content may be variedsubstantially at will, although it is advisable not to add acetone inproportions beyond approximately two parts of acetone to one part of thetotal fractions added, as otherwise the denaturant would be too dilutein character for the greatest effectiveness. The proportion of ethylalcohol added as a carrier to the column may be likewise varied withinconsiderable limits, as it will be apparent that beyond the proportionsof alcohol reasonably necesasry to obtain a proper reflux, thedenaturant is not detrimentally affected by the addition of ethylalcohol inasmuch as it is the same product as that to which thedenaturant will be later added. I have found that the ratio of from 8 to10 parts of ethyl alcohol to one part of the remaining elements added tothe column is sufllcient to obtain good refluxing conditions and,accordingly, the addition of further alcohol would merely involveloading the column with an unreasonable proportion of alcohol whichwould be a waste of heat and storage. The ethyl alcohol employed inrefluxing may be undenatured 95% ethyl alcohol, although' it will bequite apparent that one may utilize alcohol which has already beendenatured with my denaturant or even any other denaturant which does notdeleteriously affect my finished product.

While I have described preferred proportions which may be admitted tothe reflux column, in order to prepare my novel denaturant, it will bequite apparent that considerable latitude is permissible in varying theproportions of each of the three fractions entering the reflux column.For instance,- equal proportions of each of the three fractions may beemployed, or one or two of the fractions may be employed in lesseramounts, for instance, one or two of the fractions may be employed inproportions as low as approximately of the total value of the threefractions admitted. The manner in which these proportions may be variedwill be apparent to those skilled in the art once they become acquaintedwith the advantages which each of the three fractions contribute to thefinal product. It will also be apparent that by increasing theproportions of the higher boiling constituents entering the reflux, theboiling range of the flnaldenaturant will be slightly raised, at leastin its upper limit and that by introducing into the reflux, largerproportions of acetone, ethyl alcohol or other carrier, the initialboiling point of the flnal denaturant will be slightly lowered, althoughwithin the limits herein stated a large portion of the denaturantobtained will be found to distill over between and C. In most instancesat least 95% of my denaturant distills over below about C.

While above I have described ethyl alcohol as the carrier in producingmy refluxed denaturant I may employ with substantially equaleifectiveness, many other carriers of similar solvent properties towardthe fractions used, such, for instance, 'as acetone, isopropyl alcohol,isopropyl ether, ethyl methyl ketone, normal propyl alcohol, other loweralcohols (except methyl), lower ethers, and the like organic solventshaving a boiling range falling generally between 55 and 99 C. Mixturesof these may also be employed. In the event acetone is desired as thecar-- rier, it may all be added with the allyl alcohol fraction or parttherewith and part at the bottom third of the column as in the case ofthe other carriers.

Also in producing a refluxed denaturant I may use any two or even one ofthe fractions above referred to. As a two fraction reflux the allylalcohol fraction may preferably be used as one fraction and either thelight acid oil fraction or the washed alcohol oil fraction in equal orpredominating proportions used as the other. Iv

may, of course, use the two oil fractions or I may use only one of thethree fractions. Reflux conditions when employing less than threefractions are similar to those employed when all three fractions areutilized. The boiling range of the finished denaturant will, of course,vary as the heavier or lighter fractions and various carriers employedpredominate but such ranges will fall generally between about 70 and 80C.

I have found that ethyl-alcohol may be quite eiiectively denatured byemploying five parts of either the refluxed denaturant or the mixeddenaturant per one hundred parts of ethyl alcohol to be denatured. Theamount of my denaturant which may be employed depends entirely upon twofactors, namely, the minimum which may be as low as two parts or evenone part per one hundred parts of ethyl alcohol depends upon the degreeof impediment which it is desired to place in the way of the illicitalcohol trade, and the maximum which may be any amount desired dependsentirely upon the use to which the product is to be put, for instance,one would not want to add to the alcohol so much denaturant that itwould impede or obscure the useful properties of the ethyl alcoholitself, in, for instance, the lacquer industry.

Furthermore, if desired, there may be added to my denaturant variousloading compounds for various purposes. For instance, gasoline may beadded thereto in small proportions, such as 10% of the denaturant, inorder to give turbidity to any mixture of the denatured alcohol withwater. Other substances having a characteristic and desirably repulsiveodor may likewise be added to the denaturant as a warning to thepossible illicit consumer that the alcohol is entirely unfit forbeverage purposes. Various other additions may be made to my denaturantin order to give cer-.

tain additional properties thereto, such, for instance, as pinesol" andsimilar pine oil products obtained by the leaching of hogged pine woodby means of low boiling petroleum fractions. Suifice it to say, however,that these various addition agents are not necessary in any way to theeffectiveness of my denaturant and are entirely optional depending uponthe use to which the alcohol is to be put and the character of the tradethrough whose hands it passes.

Numerous other variations to my invention will be apparent to thoseskilled in the art, it being understood that the foregoing isillustrative of the manner in which my invention may be accomplished andthat it is to be in no way limited except by the claims appended hereto.

Having thus described my invention, what I claim and desire to secure byLetters Patent of the United States is: a

1. A substantially methanol-free denaturant for ethyl alcohol, the majorproportion of which boils below 85 0., comprising a light acid oilfraction the major proportion of which boils between approximately and160 C., a washed alcohol oil fraction the major proportion of whichboils between approximately 75 and 160 C., and an allyl alcohol fractionthe major proportion of which boils between approximately 66 and 91 C.,obtained from the distillation of pyroligneous crude.

2. A substantially methanol-free denaturant for ethyl alcohol, the majorproportion of which boils below C., comprising a light acid oil fractionthe major proportion of which boils between approximately 75 and 160 C.,a washed alcohol oil fraction the major proportion of which boilsbetween approximately 75 and 160 C., and an allyl alcohol fraction themajor proportion of which boils between approximately 66 and 91 C.,obtained from the distillation of pyroligneous crude, together with acarrier therefor.

3. A substantially methanol-free denaturant for ethyl alcohol, the majorproportion of which boils below 85 C., comprising a light acid oilfraction the major proportion of which boils between approximately 75and 160 C., a washed alcohol oil fraction the major proportion of whichboils between approximately 75 and 160 C., and an allyl alcohol fractionthe major proportion of which boils between approximately 66 and 91 C.,obtained from the distillation of pyroligneous crude, together withacetone.

4. A substantially methanol-free denaturant for ethyl alcohol, the majorproportion of which boils below 85" 0., comprising a light acid oilfraction the major proportion of which boils between approximately 75and 160 C., a washed alcohol oil fraction the major proportion of whichboils between approximately 75 and 160 C., and an allyl alcohol fractionthe ,major proportion of which boils between approximately 66 and. 91C., obtained from the distillation of pyroligneous crude, together withethyl alcohol.

5. A substantially methanol-free denaturant for ethyl alcohol. the majorproportion of which boils below 85 C., comprising a light acid oilfraction the major proportion of which boils between approximately 75and 160 C., a washed alcohol oil fraction the major proportion of whichboils between approximately 75 and 160 C., and an allyl alcohol fractionthe major proportion of which boils between approximately 66 and 91 C.,obtained from the distillation of pyroligneous crude, together withisopropyl alcohol.

6. A substantially methanol-free denaturant for ethyl alcohol. the majorproportion of which boils below 85 C., comprising an allyl alcoholfraction the major proportion of which boils between approximately 66and 91 C. and a fraction selected from the group consisting of a washedalcohol oil fraction the major proportion of which boils betweenapproximately 75 and 160 C. and a light acid 011 fraction the majorproportion of which boils between approximately 75 and 160 0., all ofwhich fractions are obtained fromthe distillation of pyroligneous crude.

7. A substantially methanol-free denaturant for ethyl alcohol,.the majorproportion of which boils between 70 and 80 C., comprising the productresulting from the refluxing with a carrier of a light acid oil fractionthe major proportion of which boils between approximately 75 and 160 C.,a washed alcohol 011 fraction the major proportion of which boilsbetween approximately 75 and 160 C., and an allyl alcohol fraction themajor proportion of which boils between approximately 66 and 91 C.,obtained from the distillation of pyroligneous crude.

8. A substantially methanol-free denaturant i'or ethyl alcohol, themajor proportion of which boils between 70 and 80 C., comprising theproduct resulting from the refluxing with ethyl alcohol of a light acidoil fraction the major proportion of which boils between approximately75 and 160 C., a washed alcohol oil fraction the major proportion ofwhich boils between approximately 75 and 160 C., and an allyl alcoholfraction the major proportion of which boils between approximately 66and 91 C., obtained from the distillation of pyroligneous crude.

9. A substantially methanol-free denaturant for ethyl alcohol, the majorproportion of which boils between 70 and 60 C., comprising the productresulting from the refluxing with acetone of a light acid oil fractionthe major proportion of which boils between approximately 75 and 160 C.,a washed alcohol oil fraction the major proportion of which boilsbetween approximately 75 and 160 C., and an allyl alcohol fraction themajor proportion of which boils between ap- 150 proximately 66 and 910., obtained from the distillation of pyroligneous crude.

10. A substantially methanol-free de'naturant for ethyl alcohol, themajor proportion of which boils between and 80 0., comprising theproduct resulting from the refluxing with isopropyl alcohol of a lightacid oil fraction the major proportion of which boils betweenapproximately C; and 160 C., a washed alcohol oil fraction the majorproportion of which boils between approximately 75 and 160 C., and anallyl alcohol fraction the major proportion of which boils betweenapproximately 66 and 91 0., obtained from the distillation ofpyroligneous crude.

11. The process of preparing a denaturant for ethyl alcohol, the majorproportion of which denaturant boils between 70 and 0., which comprisesrefluxing with a carrier a light acid oil fraction the major proportionof which boils between 75 and 160 C., a washed alcoholoil fraction themajor proportion of which boils between approximately 75 and 160 (2.,and an allyl alcohol fraction the major proportion of which boilsbetween approximately 66 and 91 C., obtained from the distillation ofpyroligneous crude.

12. The process of preparing a denaturant for ethyl alcohol, the majorproportion of which denaturant boilsbetween 70 and 80 C., whichcomprises refluxing with acetone a light acid oil fraction the majorproportion of which boils between 75 and 160 C.,' a'washed alcohol oilfraction the major proportion of which boils between approximately 75and 160 C., and an allyl alcohol fraction the major proportion of whichboils between approximately 66 and 91 C. obtained from the distillationof pyroligneous crude.

13. The process of preparing a denaturant for ethyl alcohol, the majorproportion of which denaturant boils between 70 and 80 0., whichcomprises refluxing with ethyl alcohol a light acid oil fraction themajor proportion of which boils between 75 and 160 C., a washed alcoholoil fraction the major proportion of which boils between approximately75 and 160 0., and an allyl alcohol fraction the major proportion ofwhich boils between approximately 66 and 91 boils between 75 and 160 C.,a washed alcohol oil fraction the major proportion of which boilsbetween approximately 75 and 160 C..'and an allyl alcohol fraction themajor proportion of which boils between approximately 66 and 91" (3.,obtained from the distillation of pyroligneous crude.

15. The process of preparing a denaturant for ethyl alcohol, the majorproportion of which denaturant boils between 70 and80 C., which icomprises refluxing with a carrier an allyl alcohol fraction the majorproportion of which boils between approximately 66 and 91 C., and afrac-p -tion selected from the group consisting of a washed alcohol oilfraction the major proportion of which boils between approximately 75and 160 C.,-and a light acid oil fraction the major proportionof whichboils between 75 and 1603 C., all of which fractions are obtained fromthe distillation of pyroligneous crude.

16. The process of preparing a denaturant for ethyl alcohol, the majorproportion of which denaturant boils between 70 and 80 C., whichcomprises refluxing with a carrier a lightacid oil fraction the majorproportion of which boils between 75 and 160 C., a washed alcohol oilfraction the major proportion of which boils between approximately 75and 160C and an allyl alcohol fraction the major proportion of whichboils between approximately 66 and 91 (3., obtained from thedistillation of pyroligneous crude, the carrier and fractions being fedinto the refluxing equipment in approximately the proportions in whichthey exist in azeotropic mixture resulting from the refluxing operation,and condensing the azeotropic mixture of vapors issuing from therefluxing operation.

LOUIS J. FIGG, JR.

CERTIFICATE ()F CORRECTION.

Patent No. l, 975, 091.

October 2, 1934.

LOUIS J. r ce, JR.

it is hereby certitied'that error appears in the printed specificationof the above numbered patent requiring correction asftollows:

Page 4, line 99, for

.'"value" read volume; and that the said Letters Patent should be readwith this correction therein that the same may conform to the record ofthe case in the Patent Office. Signed and sealed (Sell),

on; 8th day of January, A. 0,1935.

Leslie Frazer Acting Commissioner of Patents.

